Water and concentration for 2, 5 and 10 mg gonadorelin vials, the salt-form correction the labels make, and the pump trial's 1 mg/mL solution for reference.
Gonadorelin is the body's own gonadotropin-releasing hormone, and every product of it that carries a current label is a solution: five cattle products, none of which needs water. The powders that do need water are the research vials, at 2, 5 and 10 mg, and the two discontinued human products. So this page works the water arithmetic for the research vials, then sets it against the two documented reference points the labels and the one modern trial provide: the conversion from salt to peptide, and the 1 mg/mL solution Ferring programmed into its pump. All sources were read on 2026-11-12. It does the arithmetic; it suggests no amount.
The doses on record — pump pulses, the single test dose, the cattle labels and the figures on protocol pages — are on the gonadorelin dosage page, and the paired GnRH and kisspeptin tests on gonadorelin vs kisspeptin. Any vial and water volume can be worked in the gonadorelin calculator. The mixing procedure itself is on Medibact's how to reconstitute peptides, and Medibact's gonadorelin guide covers the molecule.
Water per vial and the concentration it gives
Concentration is the vial's micrograms divided by the water in millilitres. One unit on a U-100 insulin syringe is 0.01 mL.
| Vial |
1 mL |
2 mL |
3 mL |
| 2 mg (2,000 mcg) |
2,000 mcg/mL · 20 mcg/unit |
1,000 · 10 |
667 · 6.7 |
| 5 mg (5,000 mcg) |
5,000 · 50 |
2,500 · 25 |
1,667 · 16.7 |
| 10 mg (10,000 mcg) |
10,000 · 100 |
5,000 · 50 |
3,333 · 33.3 |
Units for the amounts that appear on the dosage page, at each pair:
| Vial and water |
50 mcg |
100 mcg |
250 mcg |
| 2 mg in 1 mL |
2.5 units |
5 |
12.5 |
| 2 mg in 2 mL |
5 units |
10 |
25 |
| 2 mg in 3 mL |
7.5 units |
15 |
37.5 |
| 5 mg in 1 mL |
1 unit |
2 |
5 |
| 5 mg in 2 mL |
2 units |
4 |
10 |
| 5 mg in 3 mL |
3 units |
6 |
15 |
| 10 mg in 1 mL |
0.5 units |
1 |
2.5 |
| 10 mg in 2 mL |
1 unit |
2 |
5 |
| 10 mg in 3 mL |
1.5 units |
3 |
7.5 |
Gonadorelin's documented amounts are micrograms, and the larger vials are concentrated: from a 10 mg vial in 1 mL, 50 mcg is half a unit, a volume no insulin syringe scale marks. More water gives larger, more readable volumes for the same micrograms. Portions per vial for any amount are worked on doses per vial, and the syringe scale on insulin syringe units.
What the milligrams on the vial mean
The labelled gonadorelin products state their strength two ways, and the difference is not small.
| Product (source, read 2026-11-12) |
As labelled |
As gonadorelin |
Ratio |
| Cystorelin, OvaCyst (DailyMed) |
50 mcg/mL gonadorelin diacetate tetrahydrate |
43 mcg/mL |
0.86 |
| Fertagyl (DailyMed) |
43 mcg/mL gonadorelin, as the acetate |
43 mcg/mL |
— |
| LutrePulse 3.2 mg (Ferring protocol, NCT01976728) |
3.2 mg gonadorelin acetate |
2.91 mg |
0.91 |
| Factrel human vials (Drugs@FDA) |
0.1, 0.2, 0.5 mg "EQ … BASE" |
stated as the base |
— |
Peptides are made and sold as salts, and the salt — acetate, or acetate plus water of crystallisation — adds weight without adding peptide. The labels convert so that the figure on the box is the amount of active molecule, or say plainly that it is not. A research vial marked "2 mg" usually does neither. If its 2 mg is the acetate, it holds about 1.82 mg of gonadorelin, and 2 mL gives about 909 mcg/mL instead of 1,000; if it is the diacetate tetrahydrate, about 1.72 mg and 860 mcg/mL. The arithmetic is this site's, from the ratios in the table. Every unit count above carries that uncertainty, between 9 and 14%, before any measuring error.
The pump trial's solution as a reference point
The one modern human trial of gonadorelin with its protocol on the registry is Ferring's study of LutrePulse delivered under the skin by an OmniPod pump, in 39 women with hypogonadotropic hypogonadism (NCT01976728, completed). Its protocol, amendment 7 dated 6 December 2017, describes the product exactly:
- each vial was 13.2 mg of powder containing 3.2 mg of gonadorelin acetate, equivalent to 2.91 mg of gonadorelin — so roughly three-quarters of the cake was excipient, and the weight of the powder says little about the weight of peptide;
- each came with a 10 mL vial of solvent (sodium chloride, water for injection and hydrochloric acid, pH 4.0–5.0), not bacteriostatic water;
- the pump was programmed to deliver 10, 15 or 20 µL of solution for 10, 15 or 20 µg per pulse, every 90 minutes.
Ten microlitres for ten micrograms is 1 µg per µL, a concentration of 1 mg/mL. The passages read do not state how much of the 10 mL solvent went into each vial; at 1 mg/mL a 3.2 mg vial would take 3.2 mL. The arithmetic that follows is this site's:
| Quantity |
Value |
| Pulses per day at one every 90 minutes |
16 |
| Gonadorelin per day at 10 / 15 / 20 µg a pulse |
160 / 240 / 320 µg |
| Days a 3.2 mg vial supplies at 10 / 15 / 20 µg |
20 / about 13 / 10 |
| Volume of one 10 µg pulse at 1 mg/mL |
10 µL = 1 unit on a U-100 syringe |
The research-vial set-up that reproduces that concentration is a 2 mg vial in 2 mL of water (1,000 mcg/mL); a 5 mg vial would need 5 mL and a 10 mg vial 10 mL. Matching the concentration does not reproduce the trial: its solvent was acidified saline, its doses were delivered in pulses by a programmed pump, and it was conducted under medical supervision. The figure is a reference point for the arithmetic, not a description of how a vial should be prepared.
The protocol also records why the pump doses were higher than the old intravenous ones: Ferring's own pharmacokinetic study found about 25% bioavailability under the skin compared with a vein, so the usual 5 µg intravenous pulse was expected to need about 20 µg subcutaneously.
Old human vials, research vials, cattle vials
| Product |
Form |
Gonadorelin per vial |
| Factrel (human, discontinued) |
powder |
0.1, 0.2 or 0.5 mg (as base) |
| LutrePulse kits (human, discontinued) |
powder |
0.8 or 3.2 mg (as acetate) |
| Research vials |
powder |
2, 5 or 10 mg (salt form usually unstated) |
| Factrel for cattle (current) |
solution, 50 mcg/mL |
1, 2.5 or 5 mg in 20, 50 or 100 mL |
A 2 mg research vial holds four times the largest Factrel vial; a 10 mg vial holds a hundred times the smallest. At the calculator's volumes, even the most dilute research set-up — 2 mg in 3 mL, 667 mcg/mL — is more than thirteen times the strength of the cattle solution.
What this page does not do
It does not give a dose, a schedule or a mixing protocol, and it does not describe filling a pump. The pump trial is reported because its protocol is the only modern document that states a gonadorelin concentration for human use; the figures are its, read from the registry copy. Questions about fertility treatment or hormone testing belong with a clinician.
